Security marks based on print job image

ABSTRACT

A printing system receives a print request containing patterns of marks to be printed on print media to produce printed output. A processor evaluates the print request to identify different printing densities of the patterns of marks. The processor alters the patterns of marks to create hidden features on the printed output by adding different printing densities of fluorescent spots to different areas of the patterns of marks. The different printing densities of the fluorescent spots are based on the different printing densities of the patterns of marks and on the size of the hidden features. A printing device prints the print request on the print media to produce the printed output.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present invention is related to co-pending application entitled“SECURITY MARKS BASED ON PRINT JOB IMAGE WITH UNIFORM PRINTEDBACKGROUND”, U.S. application Ser. No. 16/571,263 filed on Sep. 16,2019, the entire teachings of which are incorporated herein byreference.

BACKGROUND

Systems and methods herein generally relate to security printing andmore particularly to creating hidden marks within an image of a printjob.

Since the creation of the copy machine the authenticating and securingof documents is an area of interest in the printing industry. Watermarksof many kinds, typically in yellow toner or clear toner, have been usedwith some success. These rely on visible light effects such as gloss andreflectance. Microprinting is another security printing process, yetmicroprinting relies on the resolution and quality of the printer beingused, and hence can be costly. The use of invisible toners/inks istypical for many security applications. Yet invisible inks/toners are“invisible” and can only be used for limited purposes.

In one example, security printing features can be elements of thedocument that do not appear in the original but do appear in a copy ofthe original, which allows the holder to recognize that they do notpossess the original document. For example, the security printingfeatures may reveal “copy” or “void” in a copy of an original. Suchprinting is a popular anti-counterfeiting and anti-forging method toprotect valuable documents such as prescriptions and concert tickets.Other systems provide security printing that is visible only in theoriginal, for example only when the original is viewed under speciallighting conditions, such as ultraviolet (UV) light.

Regarding terminology for different types of light, as is understood bythose ordinarily skilled in the art, “white light” generally meanshuman-visible light such as daylight, artificial light sources(indoor/outdoor lights, mobile light sources), and is different frominfrared light, ultraviolet light, etc.). Some fluorescent toners/inks(typically yellow, green or red) are designed to transform the invisible(non-human visible) component of light into human-visible light at aspecific wavelength.

White light contains most (or all) human-visible colors, whileultraviolet light includes light wavelengths shorter than those withinthe spectrum of human-visible light. White light causes different colorsto reflect differently from the original and the copy, while ultravioletlight causes only a single color to reflect. In one example, a typicalUV (black) light is a single wavelength around 365-395 nm which is justunder the visible range (400 nm). When ultraviolet light is shined onitems that fluoresce, the fluorescent items reflects back light at alonger wavelength and therefore the fluorescent items stand outdramatically from the other non-fluorescent items that all appear darkviolet.

The color reflected back under incident black light depends on the typeof fluorescent wet or dry ink characterized by the longer wavelength.The fluorescent characteristic of fluorescent wet or dry ink willfluoresce in response to ultraviolet light much more than other ink ortoner because standard inks and toners do not contain any (or only smallamounts of) fluorescent material. For example, fluorescent inks can have10×, 50×, 100×, etc., the fluorescence to ultraviolet light relative tostandard inks and toners (e.g., RGB, CMYK, etc.). This causesfluorescent inks to appear much brighter, relative to areas of the printmedia that are covered with ink or toner, in response to ultravioletlight.

Also, relatively lighter fluorescent inks/toners (e.g., light yellow,white, light pink, etc.) have a color more similar to the sheets ofmedia, than to the relatively darker non-fluorescent inks/toners used toform the pattern of marks of the printed image. Therefore, when theoriginal is exposed to white light, the relatively lighter fluorescentinks/toners generally appear the same as the non-printing areas of theprint job image to a human observer or camera.

Further, in security printing the fluorescent inks/toners are usuallyprinted as small patches/spots that are spaced apart. This causes thefluorescent inks/toners to not be distinctly visible within the image,and instead the small and spaced fluorescent patches/spots visuallymerge together with the non-fluorescent inks/toners used to form thepattern of marks of the printed image (when the printed image is viewedwithout magnification). Thus, such small and spaced fluorescentpatches/spots are not distinctly visible when viewed in white light, andsuch small and spaced fluorescent patches/spots merely tend to lightenthe overall appearance of the printed image. However, these fluorescentpatches/spots are formed in a pattern and at a sufficient density toform a clearly visible pattern of words, symbols, or other markings whenthe printed image is viewed under ultraviolet light.

SUMMARY

Various methods herein are performed using a printing system that caninclude a processor; and a printing device, a scanner, and a feeder,etc., in communication with the processor. The methods herein receive aninitial print request that contains patterns of marks to be printed onprint media, using the processor for example.

The methods identify different printing densities of the patterns ofmarks within the print request. For example, in some embodiments, thesemethods print the initial print request on the print media using theprinting device to produce initial printed output. If so printed, thesemethods use the scanner to scan this initial printed output to produce ascan of the initial printed output. Such methods then use the processorto evaluate the scan of the initial printed output to identify differentprinting densities of the patterns of marks in the image on the initialprinted output. In other embodiments, rather than printing and scanningthe initial print request, the processor may simply be used to evaluatethe image within the print request to identify the different printingdensities of the patterns of marks within the print request itself.

With this, the methods herein use the processor to alter the patterns ofmarks in the initial print request to create a revised print requestthat has hidden features. More specifically, in this processing themethods alter the patterns of marks in the initial print request byadding different printing densities of fluorescent spots to differentareas of the patterns of marks. The different printing densities of suchfluorescent spots are created based upon the different printingdensities of the patterns of marks and based upon the size of the hiddenfeatures.

In greater detail, the processor is used in these methods to addrelatively higher printing densities of the fluorescent spots to areasof the patterns of marks having relatively higher printing densities andadd relatively lower printing densities of the fluorescent spots toareas of the patterns of marks having relatively lower printingdensities. Also, these methods add relatively lower printing densitiesof the fluorescent spots to the different areas of the patterns of marksas relative feature sizes of the hidden features formed by thefluorescent spots increases. In other words, such methodsestablish/create the different printing densities of the fluorescentspots relative to the different printing densities of the patterns ofmarks and relative to the size of the hidden features to cause thehidden features to only be visible when viewed under ultraviolet light.

In additional embodiments, these methods can use the processor toidentify different areas of the pattern of marks that are not to receivethe hidden features because the printing density and/or printing gamutmakes those areas poor candidates for hidden features.

The methods use the printing device to print the revised print request,after the processor alters the pattern of marks, to produce revisedprinted output. The methods also use the same (or a different) scannerto scan the revised printed output to produce a scan of the revisedprinted output. The methods can then use the processor to determinewhether the hidden features are visible in the scan of the revisedprinted output. Additionally, this process can be iterative, so themethods can repeat the process of altering the patterns of marks byreducing the printing densities of the fluorescent spots so long as thehidden features remain visible in each successive scan of the revisedprinted output during each iteration.

The methods can also use the processor to determine whether the revisedprint request is to be utilized or not based on whether the hiddenfeatures are visible in the scan of the revised printed output(potentially without any additional iterations). With this, the methodscan use the printing device to print either the initial print request orthe revised print request (e.g., as a production run print job).Further, the methods can use the feeder to discard the initial printedoutput, if it is not used.

Various printing systems herein perform such methods and such systemsinclude, among other components, a processor; and a printing device, ascanner, and a feeder, etc., in communication with the processor. Theprocessor can be, for example, adapted to receive the initial printrequest that contains the patterns of marks to be printed on the printmedia.

Again, these devices evaluate the print request to identify thedifferent printing densities of the patterns of marks within the imagein the print request. In some embodiments, the printing device isadapted to print the initial print request on the print media to produceinitial printed output and the internal scanner is adapted to scan thisinitial printed output to produce a scan of the initial printed output.The processor is then adapted to evaluate the scan of the initialprinted output to identify different printing densities of the patternsof marks in the image on the initial printed output. In otherembodiments, rather than printing and scanning the initial printrequest, the processor may simply evaluate the received print request toidentify the different printing densities of the patterns of markswithin the image in the print request itself.

With this, the processor is adapted to alter the patterns of marks inthe initial print request to create a revised print request that hashidden features. More specifically, the processor alters the patterns ofmarks in the initial print request by adding different printingdensities of fluorescent spots to different areas of the patterns ofmarks. Again, the different printing densities of such fluorescent spotsare formed/created based on the different printing densities of thepatterns of marks and on the size of the hidden features.

In greater detail, the processor is adapted to add relatively higherprinting densities of the fluorescent spots to areas of the patterns ofmarks having relatively higher printing densities and add relativelylower printing densities of the fluorescent spots to areas of thepatterns of marks having relatively lower printing densities. Also, theprocessor is adapted to add relatively lower printing densities of thefluorescent spots to the different areas of the patterns of marks as therelative feature sizes of the hidden features formed by the fluorescentspots increases. In other words, the processor is adapted to establishthe different printing densities of the fluorescent spots relative tothe different printing densities of the patterns of marks and the sizeof the hidden features to cause the hidden features to only be visiblewhen viewed under ultraviolet light.

This process can be iterative, so the processor is adapted toiteratively repeat the process of altering the patterns of marks byincrementally reducing the printing densities of the fluorescent spotsso long as the hidden features remain visible in the scan of the initialprinted output. In additional embodiments, the processor can be adaptedto identify different areas of the pattern of marks that are not toreceive the hidden features because the printing density and/or printinggamut makes those areas poor candidates for hidden features.

The printing device is then adapted to print the revised print requestafter the processor alters the pattern of marks to produce revisedprinted output. The same (or a different) internal scanner is adapted toscan the revised printed output to produce a scan of the revised printedoutput. The processor is adapted to determine if the revised printrequest is to be utilized based on whether the hidden features arevisible in the scan of the revised printed output. With this, theprinting device is adapted to print either the initial print request orthe revised print request as a production run print job based on whetherthe revised print request is to be utilized. Further, the feeder isadapted to discard the initial printed output if it is not used.

These and other features are described in, or are apparent from, thefollowing detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

Various exemplary systems and methods are described in detail below,with reference to the attached drawing figures, in which:

FIG. 1 is a flow diagram of various methods herein;

FIG. 2 is a schematic diagram illustrating systems herein;

FIG. 3 is a schematic diagram illustrating devices herein;

FIG. 4 is a schematic diagram illustrating devices herein;

FIGS. 5 and 6 are images illustrating printing output produced bymethods and devices herein;

FIGS. 7A-7B are schematic diagrams illustrating printed output producedby methods and devices herein; and

FIGS. 8A-8B are schematic diagrams illustrating greatly magnifiedportion of a printed output produced by methods and devices herein.

DETAILED DESCRIPTION

As mentioned above, in some security printing the difference between theprinting pattern of the original and the marks printed with fluorescentinks is only visible when the original is exposed to ultraviolet lightbecause the fluorescent inks fluoresce greatly relative to the otherinks/toners; and in contrast, under white light the fluorescent inksblend with the other colors and are not visible to the user. The systemsdescribed below use a special toner, a camera/scanner system thatreturns real time image content, and a workflow that uses that imagecontent to determine where and how much toner to apply to the image tomake hidden marks/printing when needed.

More specifically, the systems/methods herein use a fluorescent toner,an image-based system, and a workflow to produce and validate theprinting of hidden marks that allows inspection of the printed outputreal time. The system scans the image in the paper path being printed,compares that image to the source, and marks any differences as defects.The system can also stop when a defect is found and re-print the jobdefect free. The workflow determines image content (color, solids,halftones, etc.) and that information is then used to mapsecurity/invisible marks at appropriate halftone levels that best suitsthe image content.

In greater detail, FIG. 1 is flowchart illustrating exemplary methodsherein. Various methods herein are performed using a printing systemthat can include, for example, a processor; and a printing device, ascanner, and a feeder in communication with the processor and suchmethods are fully automatic (with every process described herein beingperformed automatically by machine without any human intervention) orpartially automatic and partially manual. As shown in item 100, themethods herein receive, using the processor for example, an (initial)print request (e.g., copy job, print job, production job, etc.) thatcontains patterns of marks to be printed on print media.

The methods identify different printing densities of the patterns ofmarks within the print request. For example, in some embodiments (asshown in item 102) these methods print the initial print request on theprint media using the printing device to produce initial printed output.If so printed, in item 104 these methods use the scanner (potentially aninternal scanner of the printing device) to scan this initial printedoutput to produce a scan of the initial printed output. In item 106,such methods then use the processor to evaluate the scan of the initialprinted output to identify different printing densities of the patternsof marks on the initial printed output. In other embodiments, ratherthan printing 102 and scanning 104 the initial print request, theprocessor may simply be used to evaluate the print request in item 108to identify the different printing densities of the patterns of markswithin the print request itself.

Based on the processing in items 106 and 108, these methods can thencompare the printing densities of the patterns of marks and the printinggamut (e.g., darkness) of such patterns of marks to known standards todetermine whether any aspects of the print request is a viable candidatefor adding hidden features in item 110.

Regarding such known standards, in some images the printing density andthe color of the pattern of marks may cause portions of images or entireimages to be poor candidates for hidden features. For example, poorcandidates may have sufficiently high print density and/or sufficientlydark marks as to require such a high printing density of fluorescentspots for visibility under ultraviolet light that the fluorescent spotswill also be visible under white light. Therefore, there will be somesituations where the dark color and high printing density of the patternof marks prohibits hidden features from being formed.

In view of this, the systems and methods herein evaluate the full imagethat the initial print request creates on the printed output using thepatterns of marks. Some of the areas of the image may not be goodcandidates for the hidden features, while other areas of the image maybe good candidates for the hidden features. Therefore, the systems andmethods herein limit the areas of the printed output in which hiddenfeatures can be formed to only the good candidate areas. Further, theremay be some print requests that contain very little or no good candidateareas, and those are considered as being poor candidates in an item 110,as described above.

If the print request is a viable candidate for adding hidden features,then in item 112 the methods herein use the processor to alter thepatterns of marks in the initial print request to create a revised printrequest that has hidden features. If not, processing ends, or theinitial print request is simply printed without modification in item124.

More specifically, in the processing in item 112 the methods alter thepatterns of marks in the initial print request by adding differentprinting densities of fluorescent spots to different areas of thepatterns of marks. The locations of, and different printing densitiesof, such fluorescent spots are based on (e.g., varied, controlled,changed, established, etc.) the different printing densities of thepatterns of marks and based on the size of the hidden features formed bythe pattern of the fluorescent spots.

For purposes herein, the fluorescent “spots” could by any shape andsize, such as round, rectangles, polygons, curved shaped features, etc.(e.g., dots, squares, patches, etc.). Additionally, each fluorescentspot can be large enough to be printed using multiple pixels of aprinting system (or a single pixel). Therefore, the printing density ofthe fluorescent spots can refer to the percentage of pixels print perunit area used to print each fluorescent spot (e.g., halftonepercentage, area coverage percentage, ink/toner amount per spot,fluorescent spot concentration, etc.). In other embodiments, theprinting density of the fluorescent spot can refer to how manyfluorescent spots are printed per unit area, such as per inch, permillimeter, per dot, (which can also be referred to as the density offluorescent spots per unit area of the image, fluorescent spot pitch,fluorescent spot density).

In greater detail, in item 112 the processor is used in these methods toadd relatively higher printing densities of the fluorescent spots toareas of the patterns of marks that have relatively higher printingdensities (same nomenclature as above) and add relatively lower printingdensities of the fluorescent spots to areas of the patterns of marksthat have relatively lower printing densities. Also, in item 112 thesemethods add relatively lower printing densities of the fluorescent spotsto the different areas of the patterns of marks as relative featuresizes (font size, character size, graphic size, etc.) of the hiddenfeatures formed by the fluorescent spots increases.

These methods also use the information from item 110 regarding the areasof the image identified as good/poor candidates for the hidden featuresto select areas of the pattern of marks that are, and are not, toreceive the hidden features in item 112. In other words, in items 110,112 such methods establish the locations of, and printing densities of,the fluorescent spots based upon the different printing densities of thepatterns of marks in the image in the print request, and based on thesize of the hidden features formed by the fluorescent spots, to causethe hidden features to only be visible when viewed (in the humanspectrum, unmagnified) under ultraviolet light, and not visible underwhite light.

Thus, the systems and methods herein use different densities of thefluorescent spots in different areas of the same image in order to allowthe fluorescent spots to be easily seen when viewed with ultravioletlight but not seen when viewed with white light. The ability to see thefluorescent spots in ultraviolet and white light changes depending uponwhether the fluorescent spots are added to lightly printed (low printdensity) patterns of marks within the initial print request or heavilyprinted (high print density) patterns of marks, as well as whether thefluorescent spots are printed within patterns of marks having lightcolors (e.g., yellow, pink, orange, light brown, light blue etc.) orpatterns of marks having dark colors (e.g., black, dark brown, darkblue, gray, etc.).

In other words, for a relatively higher printing density of the(non-fluorescent) pattern of marks within the initial print request, arelatively higher printing density of fluorescent spots is needed inorder to allow the fluorescent spots to stand out from the pattern ofmarks under ultraviolet light. However, the printing density of thefluorescent spots must not be increased too much, in order to preventthe fluorescent spots from being visible in white light. The same holdstrue for relatively darker colors within the initial print request,which require a relatively higher printing density of the fluorescentspots to allow the fluorescent spots to be more easily seen underultraviolet light (again as limited by the need to not increase theprinting density of the fluorescent spots so high as to cause thefluorescent spots to also be visible under white light). In contrast,the fluorescent spots more easily stand out within relatively lowerdensity, lighter non-fluorescent colors, allowing/mandating lowerdensities of fluorescent spots, so that the fluorescent spots stand outfrom the pattern of marks under ultraviolet light, yet are not bevisible in white light.

While other terminology could be utilized to describe printing density,in the examples below, printing density of the pattern of marks in theprint request is described using halftone (HT) or area coverage (AC)percentages. These percentages are the percentage of pixels that printrelative to those pixels that do not print within a given area of theimage or within a given fluorescent spot. Therefore, the higher thepercentage, the greater number of pixels print within a given area.

In one example, fluorescent yellow dry ink can be used, and thefollowing optional settings can be established. In this example, formarks in areas of the initial print request (e.g., image content) thathave greater than 95% printing density of a dark gamut (e.g., black),hidden features are not suitable; for marks in the area of the initialprint request between 80-95% printing density of a dark gamut, hiddenfeatures are printed using 50% printing density for the fluorescentspots; for marks in the area of the initial print request between 25-50%area coverage of a dark gamut, hidden features are printed using 25%printing density for the fluorescent spots; for marks in the area of theinitial print request less than 25% area coverage of a dark gamut,hidden features are printed using 10% printing density for thefluorescent spots. Note that in the foregoing example, those ordinarilyskilled in the art would understand that other settings could beestablished for similar or different color fluorescent inks, dependingupon the paper utilized, the printer, the security application, etc.

In item 114, the methods use the printing device to print the revisedprint request, after the processor alters the pattern of marks, toproduce revised printed output. These methods also use the scanner initem 116 to scan the revised printed output under white light to producea scan of the revised printed output. In item 118, these methods use theprocessor to determine whether the hidden features are visible in thescan of the revised printed output. As shown in FIG. 1, if the hiddenfeatures are visible, processing can end, or the initial print requestcan be printed without modification in item 124.

Additionally, this processing can be iterative. Therefore, as shown inthe return arrow from item 118 to item 112 in FIG. 1, if the hiddenfeatures are visible in the scan of the revised printed output in item118, processing can flow back to item 112 to allow these methods torepeat the process of altering the patterns of marks (112) byincrementally reducing (or further reducing in subsequent iterations)the printing densities of the fluorescent spots. This iterativeprocessing can be omitted or can be repeated until the hidden featuresare no longer visible in the scan of the revised printed output.Additionally, a minimum printing density of the fluorescent spots can beset to limit how many iterations are performed. For example, the minimumprinting density can be a limit below which the hidden features are toofaint and are no longer reliably visible under ultraviolet light. Ifthis minimum printing density of the fluorescent spots is reached butthe hidden features are still visible, this indicates that the affectedportion of the pattern of marks (or the entire pattern of marks) is nota viable hidden feature candidate and processing can end or the initialprint request can be printed without modification in item 124.

Next, in item 120, the methods can then use the processor to determineif the revised print request is to be utilized at all, based on whetherthe hidden features are visible in the scan of the revised printedoutput 118 (possibly when the minimum printing density has been reachedin the iterations, etc.). Therefore, in item 120, these methods can ratehow good of a candidate the pattern of marks is for hidden featuresbased on the how close the printing density of the fluorescent spots isto the minimum printing density (being closer to the minimum reducescandidate quality rank), how much area of image formed by the pattern isa good hidden feature candidate (less useful area reduces candidatequality rank), whether the desired size of the hidden features will fitwithin the good hidden feature candidate areas of the pattern of marks,how well the hidden features stand out under ultraviolet light (once thehidden features are not visible in item 118), etc. With this, themethods can use the printing device to print either the revised printrequest 122 or the initial print request 124 as a production run printjob based on whether the revised print request is to be utilized in item120. Further, in item 126 the methods can use the feeder to discard theinitial printed output if it is not used.

As shown in FIG. 2, exemplary systems and methods herein include variouscomputerized devices 200, 204 located at various different physicallocations 206. The computerized devices 200, 204 can include printservers, printing devices, personal computers, etc., and are incommunication (operatively connected to one another) by way of a localor wide area (wired or wireless) network 202.

FIG. 3 illustrates a computerized device 200, which can be used withsystems and methods herein and can comprise, for example, a printserver, a personal computer, a portable computing device, etc. Thecomputerized device 200 includes a controller/tangible processor 216 anda communications port (input/output) 214 operatively connected to thetangible processor 216 and to the computerized network 202 external tothe computerized device 200. Also, the computerized device 200 caninclude at least one accessory functional component, such as a graphicaluser interface (GUI) assembly 212. The user may receive messages,instructions, and menu options from, and enter instructions through, thegraphical user interface or control panel 212.

The input/output device 214 is used for communications to and from thecomputerized device 200 and comprises a wired device or wireless device(of any form, whether currently known or developed in the future). Thetangible processor 216 controls the various actions of the computerizeddevice. A non-transitory, tangible, computer storage medium device 210(which can be optical, magnetic, capacitor based, etc., and is differentfrom a transitory signal) is readable by the tangible processor 216 andstores instructions that the tangible processor 216 executes to allowthe computerized device to perform its various functions, such as thosedescribed herein. Thus, as shown in FIG. 3, a body housing has one ormore functional components that operate on power supplied from analternating current (AC) source 220 by the power supply 218. The powersupply 218 can comprise a common power conversion unit, power storageelement (e.g., a battery, etc.), etc.

FIG. 4 illustrates a computerized device that is a printing device 204,which can be used with systems and methods herein and can comprise, forexample, a printer, copier, multi-function machine, multi-functiondevice (MFD), etc. The printing device 204 includes many of thecomponents mentioned above and at least one marking device (printingengine(s)) 240 operatively connected to a specialized image processor224 (that is different from a general purpose computer because it isspecialized for processing image data), a media path 236 positioned tosupply continuous media or sheets of media from a sheet supply 230 tothe marking device(s) 240, etc. After receiving various markings fromthe printing engine(s) 240, the sheets of media can optionally pass to afinisher 234 which can fold, staple, sort, etc., the various printedsheets. Also, the printing device 204 can include at least one accessoryfunctional component (such as a scanner/document handler 232 (automaticdocument feeder (ADF)), etc.) that also operate on the power suppliedfrom the external power source 220 (through the power supply 218).

The one or more printing engines 240 are intended to illustrate anymarking device that applies a marking material (toner, inks, etc.) tocontinuous media or sheets of media, whether currently known ordeveloped in the future and can include, for example, devices that use aphotoreceptor belt or an intermediate transfer belt, or devices thatprint directly to print media (e.g., inkjet printers, ribbon-basedcontact printers, etc.).

As would be understood by those ordinarily skilled in the art, theprinting device 204 shown in FIG. 4 is only one example and the systemsand methods herein are equally applicable to other types of printingdevices that may include fewer components or more components. Forexample, while a limited number of printing engines and paper paths areillustrated in FIG. 4, those ordinarily skilled in the art wouldunderstand that many more paper paths and additional printing enginescould be included within any printing device used with systems andmethods herein.

Thus, printing systems herein include, among other components, aprocessor 216, 224; and a printing device 204, 240, an external scanner232, an internal scanner 238, and a feeder 236 in communication with theprocessor 216, 224. The processor 216, 224 is, for example, adapted toreceive an initial print request that contains patterns of marks to beprinted on print media. Again, all processes described can be fullyautomatic or partially manual, partially automatic.

In some embodiments, the printing device 204, 240 is adapted to printthe initial print request on the print media to produce initial printedoutput and the scanner 232, 238 is adapted to scan this initial printedoutput to produce a scan of the initial printed output.

The processor 216, 224 is then adapted to evaluate the scan of theinitial printed output to identify different printing densities of thepatterns of marks in the initial printed output. In other embodiments,rather than printing and scanning the initial print request, theprocessor 216, 224 may simply evaluate the print request itself (e.g.,the electronic file data) to identify the different printing densitiesof the patterns of marks within the print request, without performingany printing.

With this, the processor 216, 224 is adapted to alter the patterns ofmarks in the initial print request to create a revised print requestthat has hidden features. More specifically, the processor 216, 224alters the patterns of marks in the initial print request by addingdifferent printing densities of fluorescent spots to different areas ofthe patterns of marks. The different printing densities of suchfluorescent spots are based on the different printing densities of thepatterns of marks and on the size of the hidden features.

In greater detail, the processor 216, 224 is adapted to add relativelyhigher printing densities of the fluorescent spots to areas of thepatterns of marks having relatively higher printing densities of thepatterns of marks and add relatively lower printing densities of thefluorescent spots to areas of the patterns of marks having relativelylower printing densities of the patterns of marks. Also, the processor216, 224 is adapted to add relatively lower printing densities of thefluorescent spots to the different areas of the patterns of marks asrelative feature sizes of the hidden features formed by the fluorescentspots increases. In other words, the processor 216, 224 is adapted toestablish the different printing densities of the fluorescent spotsrelative to the different printing densities of the patterns of marksand the size of the hidden features to cause the hidden features to onlybe visible when viewed under ultraviolet light.

The printing device 204, 240 is then adapted to print the revised printrequest after the processor 216, 224 alters the pattern of marks toproduce revised printed output. The scanner 232 is adapted to scan therevised printed output to produce a scan of the revised printed output.The processor 216, 224 is adapted to determine if the revised printrequest is to be utilized based on whether the hidden features arevisible in the scan of the revised printed output.

This process can be iterative, so the processor 216, 224 is adapted torepeat altering the patterns of marks by reducing the printing densitiesof the fluorescent spots based on the hidden features being visible inthe scan of the initial printed output. In additional embodiments, theprocessor 216, 224 can be adapted to identify ones of the differentareas of the pattern of marks that are not to receive the hiddenfeatures because the printing density and/or printing gamut makes thoseareas poor candidates for hidden features.

With this, the printing device 204, 240 is adapted to print either theinitial print request or the revised print request as a production runprint job based on whether the revised print request is to be utilized.Further, the feeder 236 is adapted to discard the initial printed outputif it is not used. Note that, depending upon the diversity of ink/tonerstorage and print heads, the printer may print the fluorescent andnon-fluorescent marks in a single (the same) printing pass, or inmultiple printing passes.

FIGS. 5 and 6 illustrate examples of different output produced bymethods and systems herein. FIG. 5 shows the same background pattern ofmarks viewed under ultraviolet light with added: relatively lowerdensity fluorescent spots 302, 312; relatively somewhat higher densityfluorescent spots 304, 314; and relatively even higher densityfluorescent spots 306, 316. The fluorescent spots 302, 304, 306 havesmaller features relative to the feature sizes of the hidden featuresformed by the fluorescent spots 312, 314, 316.

As shown in FIG. 5, both feature sizes of the relatively lower densityfluorescent spots 302, 312 are only visible when viewed underultraviolet light, and are only slightly visible under ultravioletlight, if at all. Similarly, the relatively somewhat higher densityfluorescent spots 304, 314 are only visible when viewed underultraviolet light, but are move visible under ultraviolet light thanfluorescent spots 302, 312. Note that, as shown in FIG. 5, thesmaller-size features of the fluorescent spots 304 causes them to beonly slightly visible under ultraviolet light; while, in contrast, thelarger feature size of the fluorescent spots 314 allows them to be moreeasily seen under ultraviolet light. The increased printing density ofthe small feature size fluorescent spots 306 allows them to be moreeasily seen; however, again only when viewed with ultraviolet light.However, the increased printing density of the larger feature sizefluorescent spots 316 causes them to be visible under both ultravioletand white light, making the printing density and feature size of thelarger feature fluorescent spots 316 a poor candidate for hiddenfeatures within this pattern of marks.

FIG. 6 shows some real-world examples of using methods and systemsherein. Items 322 and 324 show the same sporting event ticket viewedunder ultraviolet light (322) and white light (324). As can be seen inFIG. 6, hidden text “Official Ticket” can be only seen when the ticketis viewed with ultraviolet light 322 and not when viewed with whitelight 324. Similarly, items 332 and 334 show the same sporting eventticket viewed under ultraviolet light (332) and white light (334). Ascan be seen in FIG. 6, hidden text “Football Tournament 2018” can beonly seen when the ticket is viewed with ultraviolet light 332 and isnot seen when viewed with white light 334.

FIGS. 7A-7B show a different exemplary image (that could be includedwithin a print request) on printed output 350, 358. The image andprinted output 350, 358 include a pattern of markings 352 that forms upand down arrow marks and the words “Elevator Access Pass.” FIG. 7A showsthe printed output 350 when viewed under white light 360. FIG. 7Billustrates the same printed output 350 shown in FIG. 7A but when viewedunder ultraviolet light 362, which allows the hidden text 354 (therepeating word “valid”) to be slightly visible.

FIGS. 8A-8B illustrate a greatly magnified portion of a printed output380 that includes a portion of a pattern of marks 352 and fluorescentspots forming hidden features 354A, 354B. The magnified printed output380 is shown at a magnification much greater than that obtainable withunaided human vision. Note that in FIGS. 8A-8B the magnification isgreat enough to allow the halftoning utilization to be observed wherecontinuous marks are not formed on the print media, button insteadclosely spaced dots or spots form the different marks shown on theprinted output 380. FIG. 8A illustrates the magnified printed output 380viewed under white light 360, while FIG. 8B illustrates the magnifiedprinted output 380 viewed under ultraviolet light 362.

As can be seen under magnification in FIG. 8A, the printing density ofthe hidden features 354A, 354B is different in the areas 354A where thepattern of marks 352 exist and the non-marking areas 354B. As notedabove, the hidden features 354A have a higher density of fluorescentspots in areas where the pattern of marks 352 exist, relative to thehidden features 354B in non-marking areas, and this allows the hiddenfeatures 354A to stand out more prominently from the pattern of marks352 when viewed under ultraviolet light (as shown in FIG. 8B). However,as can be seen in FIG. 8A, the fluorescent spots forming the hiddenfeatures 354A, 354B disturb the background and pattern of marks 352 onlyslightly, and such is not visible when the printed output is viewedunder white light 360 without the magnification shown in FIG. 8A.

While some exemplary structures are illustrated in the attacheddrawings, those ordinarily skilled in the art would understand that thedrawings are simplified schematic illustrations and that the claimspresented below encompass many more features that are not illustrated(or potentially many less) but that are commonly utilized with suchdevices and systems. Therefore, Applicants do not intend for the claimspresented below to be limited by the attached drawings, but instead theattached drawings are merely provided to illustrate a few ways in whichthe claimed features can be implemented.

Many computerized devices are discussed above. Computerized devices thatinclude chip-based central processing units (CPU's), input/outputdevices (including graphic user interfaces (GUI), memories, comparators,tangible processors, etc.) are well-known and readily available devicesproduced by manufacturers such as Dell Computers, Round Rock Tex., USAand Apple Computer Co., Cupertino Calif., USA. Such computerized devicescommonly include input/output devices, power supplies, tangibleprocessors, electronic storage memories, wiring, etc., the details ofwhich are omitted herefrom to allow the reader to focus on the salientaspects of the systems and methods described herein. Similarly,printers, copiers, scanners and other similar peripheral equipment areavailable from Xerox Corporation, Norwalk, Conn., USA and the details ofsuch devices are not discussed herein for purposes of brevity and readerfocus.

The terms printer or printing device as used herein encompasses anyapparatus, such as a digital copier, bookmaking machine, facsimilemachine, multi-function machine, etc., which performs a print outputtingfunction for any purpose. The details of printers, printing engines,etc., are well-known and are not described in detail herein to keep thisdisclosure focused on the salient features presented. The systems andmethods herein can encompass systems and methods that print in color,monochrome, or handle color or monochrome image data. All foregoingsystems and methods are specifically applicable to electrostatographicand/or xerographic machines and/or processes.

A print job includes a set of data that is to be printed, and caninclude images, graphics, and text from a variety of formats. Inaddition to the print data that will actually be printed on the printmedia, the print job also includes various commands controlling theprinting; and such commands identify the printer to be used, theresolution of printing, the media type and size to be used, colorcharacteristics, gloss characteristics, finishing operations to beperformed, destinations of the printed pages, etc. A raster imageprocessor (RIP) is a component used in a printing system that produces araster image also known as a bitmap from the print job. The bitmap isthen sent to a printing device for output. Raster image processing isthe process that turns vector digital information into a high-resolutionraster image.

An image input device is any device capable of obtaining color pixelvalues from a color image. The set of image input devices is intended toencompass a wide variety of devices such as, for example, digitaldocument devices, computer systems, memory and storage devices,networked platforms such as servers and client devices which can obtainpixel values from a source device, and image capture devices. The set ofimage capture devices includes scanners, cameras, photography equipment,facsimile machines, photo reproduction equipment, digital printingpresses, xerographic devices, and the like. A scanner is one imagecapture device that optically scans images, print media, and the like,and converts the scanned image into a digitized format. Common scanningdevices include variations of the flatbed scanner, generally known inthe arts, wherein specialized image receptors move beneath a platen andscan the media placed on the platen. Modern digital scanners typicallyincorporate a charge-coupled device (CCD) or a contact image sensor(CIS) as the image sensing receptor(s). The scanning device produces asignal of the scanned image data. Such a digital signal containsinformation about pixels such as color value, intensity, and theirlocation within the scanned image.

Further, an image output device is any device capable of rendering theimage. The set of image output devices includes digital documentreproduction equipment and other copier systems as are widely known incommerce, photographic production and reproduction equipment, monitorsand other displays, computer workstations and servers, including a widevariety of color marking devices, and the like.

To render an image is to reduce the image data (or a signal thereof) toviewable form; store the image data to memory or a storage device forsubsequent retrieval; or communicate the image data to another device.Such communication may take the form of transmitting a digital signal ofthe image data over a network.

A contone (continuous tone) is a characteristic of a color image suchthat the image has all the values (0 to 100%) of gray (black/white) orcolor in it. A contone can be approximated by millions of gradations ofblack/white or color values. The granularity of computer screens (i.e.,pixel size) can limit the ability to display absolute contones. The termhalftoning refers to a process of representing a contone image as abi-level image such that, when viewed from a suitable distance, thebi-level image gives the same impression as the contone image.Halftoning reduces the number of quantization levels per pixel in adigital image. Over the long history of halftoning, a number ofhalftoning techniques have been developed which are adapted fordifferent applications.

Traditional clustered dot halftones were restricted to a singlefrequency because they were generated using periodic gratings that couldnot be readily varied spatially. Halftoning techniques are widelyemployed in the printing and display of digital images and are usedbecause the physical processes involved are binary in nature or becausethe processes being used have been restricted to binary operation forreasons of cost, speed, memory, or stability in the presence of processfluctuations. Classical halftone screening applies a mask of thresholdvalues to each color of the multi-bit image. Thresholds are stored as amatrix in a repetitive pattern. Each tile of the repetitive pattern ofthe matrix is a halftone cell. Digital halftones generated usingthreshold arrays that tile the image plane were originally designed tobe periodic for simplicity and to minimize memory requirements. With theincrease in computational power and memory, these constraints becomeless stringent. Digital halftoning uses a raster image or bitmap withinwhich each monochrome picture element or pixel may be ON or OFF (ink orno ink).

In addition, terms such as “right”, “left”, “vertical”, “horizontal”,“top”, “bottom”, “upper”, “lower”, “under”, “below”, “underlying”,“over”, “overlying”, “parallel”, “perpendicular”, etc., used herein areunderstood to be relative locations as they are oriented and illustratedin the drawings (unless otherwise indicated). Terms such as “touching”,“on”, “in direct contact”, “abutting”, “directly adjacent to”, etc.,mean that at least one element physically contacts another element(without other elements separating the described elements). Further, theterms automated or automatically mean that once a process is started (bya machine or a user), one or more machines perform the process withoutfurther input from any user. Additionally, terms such as “adapted to”mean that a device is specifically designed to have specialized internalor external components that automatically perform a specific operationor function at a specific point in the processing described herein,where such specialized components are physically shaped and positionedto perform the specified operation/function at the processing pointindicated herein (potentially without any operator input or action). Inthe drawings herein, the same identification numeral identifies the sameor similar item.

It will be appreciated that the above-disclosed and other features andfunctions, or alternatives thereof, may be desirably combined into manyother different systems or applications. Various presently unforeseen orunanticipated alternatives, modifications, variations, or improvementstherein may be subsequently made by those skilled in the art which arealso intended to be encompassed by the following claims. Unlessspecifically defined in a specific claim itself, steps or components ofthe systems and methods herein cannot be implied or imported from anyabove example as limitations to any particular order, number, position,size, shape, angle, color, or material.

What is claimed is:
 1. A printing system comprising: a processor adaptedto evaluate a print request to identify different printing densities ofpatterns of marks in the print request to be printed on print media toproduce printed output; and a printing device in communication with theprocessor, wherein the processor is adapted to alter the patterns ofmarks to create hidden features on the printed output by addingdifferent printing densities of fluorescent spots to different areas ofthe patterns of marks, wherein the different printing densities offluorescent spots are based on the different printing densities of thepatterns of marks and on a size of the hidden features, and wherein theprinting device is adapted to print the print request on the print mediato produce the printed output after the processor alters the patterns ofmarks.
 2. The printing system according to claim 1, wherein theprocessor is adapted to add relatively higher printing densities of thefluorescent spots to areas of the patterns of marks having relativelyhigher printing densities of the patterns of marks and add relativelylower printing densities of the fluorescent spots to areas of thepatterns of marks having relatively lower printing densities of thepatterns of marks.
 3. The printing system according to claim 1, whereinthe processor is adapted to add relatively lower printing densities ofthe fluorescent spots to the different areas of the patterns of marks asrelative feature sizes of the hidden features formed by the fluorescentspots increases.
 4. The printing system according to claim 1, whereinthe processor is adapted to establish the different printing densitiesof the fluorescent spots relative to the different printing densities ofthe patterns of marks and the size of the hidden features to cause thehidden features to only be visible when viewed under ultraviolet light.5. The printing system according to claim 1, wherein the processor isadapted to identify ones of the different areas of the pattern of marksto not receive the hidden features based on the printing density andprinting gamut of the different areas of the pattern of marks.
 6. Theprinting system according to claim 1, further comprising a scanner incommunication with the processor, wherein the scanner is adapted to scanthe printed output to produce a scan of the printed output; wherein theprocessor is adapted to determine if the hidden features are visible inthe scan of the printed output; and wherein the processor is adapted torepeat altering the patterns of marks by reducing printing densities ofthe fluorescent spots based on the hidden features being visible in thescan of the printed output.
 7. The printing system according to claim 6,further comprising a feeder in communication with the processor, whereinthe feeder is adapted to discard the printed output based on the hiddenfeatures being visible in the scan of the printed output; and whereinthe printing device is adapted to repeat printing the print requestafter the printing densities of the fluorescent spots have been reduced.8. A printing system comprising: a processor adapted to receive aninitial print request containing patterns of marks to be printed onprint media; a printing device in communication with the processor,wherein the printing device is adapted to print the initial printrequest on the print media to produce initial printed output; and ascanner in communication with the processor, wherein the scanner isadapted to scan the initial printed output to produce a scan of theinitial printed output, wherein the processor adapted to evaluate thescan of the initial printed output to identify different printingdensities of the patterns of marks in the initial printed output,wherein the processor is adapted to alter the patterns of marks in theinitial print request to create a revised print request having hiddenfeatures by adding different printing densities of fluorescent spots todifferent areas of the patterns of marks, wherein the different printingdensities of fluorescent spots are based on the different printingdensities of the patterns of marks and on a size of the hidden features,wherein the printing device is adapted to print the revised printrequest after the processor alters the pattern of marks to producerevised printed output, wherein the scanner is adapted to scan therevised printed output to produce a scan of the revised printed output,wherein the processor is adapted to determine if the revised printrequest is to be utilized based on whether the hidden features arevisible in the scan of the revised printed output, and wherein theprinting device is adapted to print either the initial print request orthe revised print request as a production run print job based on whetherthe revised print request is to be utilized.
 9. The printing systemaccording to claim 8, wherein the processor is adapted to add relativelyhigher printing densities of the fluorescent spots to areas of thepatterns of marks having relatively higher printing densities of thepatterns of marks and add relatively lower printing densities of thefluorescent spots to areas of the patterns of marks having relativelylower printing densities of the patterns of marks.
 10. The printingsystem according to claim 8, wherein the processor is adapted to addrelatively lower printing densities of the fluorescent spots to thedifferent areas of the patterns of marks as relative feature sizes ofthe hidden features formed by the fluorescent spots increases.
 11. Theprinting system according to claim 8, wherein the processor is adaptedto establish the different printing densities of the fluorescent spotsrelative to the different printing densities of the patterns of marksand the size of the hidden features to cause the hidden features to onlybe visible when viewed under ultraviolet light.
 12. The printing systemaccording to claim 8, wherein the processor is adapted to identify onesof the different areas of the pattern of marks to not receive the hiddenfeatures based on the printing density and printing gamut of thedifferent areas of the pattern of marks.
 13. The printing systemaccording to claim 8, wherein the processor is adapted to repeataltering the patterns of marks by reducing the printing densities of thefluorescent spots based on the hidden features being visible in the scanof the initial printed output.
 14. The printing system according toclaim 8, further comprising a feeder in communication with theprocessor, wherein the feeder is adapted to discard the initial printedoutput.
 15. A method comprising: receiving, into a printing system, aprint request containing patterns of marks to be printed on print mediato produce printed output; evaluating the print request using aprocessor of the printing system to identify different printingdensities of the patterns of marks; altering the patterns of marks usingthe processor to create hidden features on the printed output by addingdifferent printing densities of fluorescent spots to different areas ofthe patterns of marks, wherein the different printing densities offluorescent spots are based on the different printing densities of thepatterns of marks and on a size of the hidden features; and printing theprint request on the print media using a printing device of the printingsystem to produce the printed output.
 16. The method according to claim15, wherein the altering further comprises adding relatively higherprinting densities of the fluorescent spots to areas of the patterns ofmarks having relatively higher printing densities of the patterns ofmarks and adding relatively lower printing densities of the fluorescentspots to areas of the patterns of marks having relatively lower printingdensities of the patterns of marks.
 17. The method according to claim15, wherein the altering further comprises adding relatively lowerprinting densities of the fluorescent spots to the different areas ofthe patterns of marks as relative feature sizes of the hidden featuresformed by the fluorescent spots increases.
 18. The method according toclaim 15, wherein the altering further comprises establishing thedifferent printing densities of the fluorescent spots relative to thedifferent printing densities of the patterns of marks and the size ofthe hidden features to cause the hidden features to only be visible whenviewed under ultraviolet light.
 19. The method according to claim 15,wherein the altering further comprises identifying ones of the differentareas of the pattern of marks to not receive the hidden features basedon the printing density and printing gamut of the different areas of thepattern of marks.
 20. The method according to claim 15, furthercomprising: scanning the printed output using a scanner of the printingsystem to produce a scan of the printed output; determining if thehidden features are visible in the scan of the printed output; andrepeating the altering by reducing the printing densities of thefluorescent spots based on the hidden features being visible in the scanof the printed output.